The present invention relates to an amplifier for use with a local oscillator, and more particularly to such an amplifier for amplifying an oscillated output from a local oscillator circuit which is to be applied to a mixer circuit in a frequency converter.
Conventional amplifiers for use with local oscillators in frequency converters such as CATV (community antenna television) converters have a large amplification level at an intermediate frequency band, and hence suffer from increased noise components in proportion with the amplification level and make the NF (noise figure) of the converter quite poor. Since the amplification level and hence the harmonic level are greater on reception of lower frequencies than on reception of higher frequencies, the disturbing beat is increased and appears at the input terminal of the amplifier when lower frequencies are received.